The invention relates generally to corner cubes and more particularly to an amplitude of a beam of light output by a corner cube.
Light emitters are employed in a variety of optical systems. A laser is one example of a light emitter. Exemplary uses of the laser comprise sensing, detection, measurement, and alignment in an optical system. For example, the optical system is in alignment when a laser beam that enters the system is reflected and exits the system in a path parallel to the path of the incoming laser beam. In a high power laser system, for example, the reflected beam of light is attenuated to avoid damaging a sensor device, such as a power detector. The laser system in one example comprises a corner cube retro-reflector and a filter. The corner cube retro-reflector in one example serves to reflect the incoming beam of light. The filter in one example serves to attenuate the reflected beam of light.
The corner cube retro-reflector in one example comprises three orthogonal high-reflectivity surfaces. The corner cube retro-reflector receives an input beam of light and outputs an output beam of light. The input beam of light comprises an amplitude and an intensity. The output beam of light comprises an amplitude and an intensity. The input beam of light sequentially reflects off the three surfaces of the corner cube retro-reflector. The output beam of light of the corner cube retro-reflector travels on a path parallel to that of the incoming beam of light of the corner cube retro-reflector. The output beam of light of the corner cube retro-reflector comprises the same amplitude and the same intensity as the amplitude and the intensity of the input beam of light to the corner cube retro-reflector.
The filter receives an input beam of light and outputs an output beam of light. The input beam of light comprises an amplitude and an intensity. The output beam of light comprises an amplitude and an intensity. The amplitude of the output beam of light is less than the amplitude of the input beam of light. The intensity of the output beam of light is less than the intensity of the input beam of light since the intensity of light is proportional to the square of the amplitude.
The corner cube retro-reflector is located anywhere in the optical system. For example, the corner cube retro-reflector is located at the end of the optical system. The filter is located anywhere in the optical system. For example, the filter is located at the opening of the corner cube retro-reflector. One shortcoming of the optical system results from the spatial distance between the filter and the reflective points of the sides of the corner cube retro-reflector. The distance between the filter and the reflective points of the sides of the corner cube retro-reflector contributes to the introduction of alignment errors between the input beam of light and the output beam of light of the optical system.
One implementation of the invention encompasses an apparatus. The apparatus in one example comprises a corner cube that comprises a first side, a second side, and a third side that cooperate to retro-reflect an incoming beam of light and output an outgoing beam of light. One or more of the first side, the second side, and the third side of the corner cube serve to contribute substantially to a decrease of over twenty percent in an amplitude of the outgoing beam of light relative to an amplitude of the incoming beam of light.
Another implementation of the invention encompasses a method. An amplitude of an outgoing beam of light is decreased relative to an amplitude of an incoming beam of light by over twenty percent through substantial contribution by one or more of a first side, a second side, and a third side of a corner cube that cooperate to retro-reflect the incoming beam of light and output the outgoing beam of light.